Asbestos-containing materials and where they are found in buildings
Domain 2 - Asbestos-containing materials and where they are found in buildings
This domain tests material recognition: what makes a material ACM, how friability and category change handling, and where asbestos hides in older buildings. The exam expects you to classify a material before you apply a work practice or threshold.
Definitions that drive the answer
- ACM contains more than 1% asbestos by weight, the NESHAP and OSHA convention used on the exam.
- Friable means crumbled, pulverized, or reduced to powder by hand pressure when dry.
- RACM includes friable ACM and nonfriable ACM that will be sanded, ground, cut, or otherwise damaged so it may release fibers.
- Category I nonfriable includes floor tile, mastic, gaskets, and roofing felt; Category II includes some roofing and cement products. Category I that is not damaged is not RACM, but cutting or grinding can make it RACM.
Where it is found
Thermal system insulation, surfacing materials such as sprayed fireproofing and acoustical plaster, and miscellaneous materials such as floor tile and mastic, ceiling tiles, joint compound, window glazing, roofing, cement pipe, gaskets, brake linings, and vermiculite insulation. In older buildings, TSI and surfacing materials are presumed ACM until sampling by a qualified inspector proves otherwise.
Worked example
A 1975 office renovation will disturb 300 linear feet of friable pipe insulation, 1,200 square feet of 9-inch floor tile with black mastic, and 400 square feet of ceiling tile. The pipe insulation is friable RACM; 300 linear feet exceeds the 260-linear-foot threshold, so this is a regulated renovation. The floor tile is Category I nonfriable; if removed intact it is not RACM, but if the contractor plans to grind the mastic or sand the tile, that portion becomes RACM. The ceiling tile must be sampled or presumed; do not assume it is ACM. The reasoning separates friability, category, and the planned disturbance.
Traps that cost marks
- Assuming nonfriable means not regulated even when the method will break it.
- Missing mastic and joint compound as ACM.
- Treating 1% as a safe cutoff rather than a definitional threshold.
- Forgetting that TSI and surfacing materials can be presumed ACM.
- Classifying ceiling tile without sampling or documentation.